This relates to image sensors and, more particularly, to solid-state image sensor arrays that incorporate pixels with an active reset.
Modern electronic devices such as cellular telephones, cameras, and computers often use digital image sensors. Image sensors (sometimes referred to as imagers) may be formed from a two-dimensional array of image sensing pixels. Each pixel includes a photosensitive region that receives incident photons (light) and converts the photons into electrical signals. Image sensors are sometimes designed to provide images to electronic devices using a Joint Photographic Experts Group (JPEG) format.
Image sensors may sense light by converting impinging photons into electrons or holes that are integrated (collected) in sensor pixels. After completion of an integration cycle, collected charge is converted into a voltage, which is then supplied to the output terminals of the sensor. After charge to voltage conversion is completed and the resulting signal transferred out from the pixels, the pixels may be reset in order to be ready for accumulation of new charge. However, resetting the pixels may generate kTC reset noise.
It would therefore be desirable to provide improved pixels with minimized pixel kTC reset noise.